The Gender Prediction Blog
Honest, research-backed guides to every way people guess a baby’s sex — the science, the folklore and exactly how much to trust each. No false promises, just good information and a bit of fun.
Start here
New to this? Read when you can actually find out and which methods are accurate. Want to play? Try the Chinese chart or the old wives’ tales quiz.
Editor’s picks
All 11 methods, compared
NIPT, ultrasound, chart, Ramzi and the folklore, side by side with real accuracy figures.
DataWhat the research shows
Original accuracy analysis across every popular prediction method.
Accuracy & the real answers
How Accurate Are Gender Predictors? Real Data & Research
Nub theory (~70–91%), the Chinese chart (~50%) and every method, measured against actual births.
Gender Predictor Methods Compared: Which Is Most Accurate?
A side-by-side of 11 methods from medical tests to old wives’ tales.
When Can You Tell Baby Gender? Timeline 10–20 Weeks
NIPT, nub, anatomy scan and CVS — what you can do each week and how sure it is.
The science of sex determination
How a Baby’s Sex Is Actually Decided
X and Y chromosomes at fertilisation, and the medical tests that can read them early.
Ultrasound & early methods
Nub Theory at 12 Weeks: Boy vs Girl Guide
The genital tubercle angle, how early it works and how far to trust it.
Ramzi Theory: Reading Your Ultrasound
The 6–8 week placenta-side claim, and why it is unproven.
Skull Theory for Gender Prediction
Round versus square head shape — the idea, and the reality.
Traditional & at-home fun
How Accurate Is the Chinese Gender Chart?
700 years of history, a grid of ages and months, and what the data really says.
15 Old Wives’ Tales for Baby Gender
Cravings, belly shape, heart rate and more — the complete folklore list.
Baking Soda Gender Test: Does It Work?
The fizzy at-home experiment explained by plain chemistry.
Ring Test for Gender Prediction
The pendulum swing and the ideomotor effect behind it.
Reveals & celebration
25 Creative Gender Reveal Ideas for 2026
From balloon pops and cake cuts to smoke and intimate surprises.
Try every method in one place
The main predictor blends all nine methods into one honest, weighted guess — free and private.
Open the predictor See accuracy data